Multilayer composite body

ABSTRACT

Disclosed is a multi-layer composite body comprising a flexible auxiliary support and separating layer disposed on at least one side of the auxiliary support, which modifies the complete separation or the locally determined detachment of a functional layer which is in the superficial contact thereto. Said body is characterized in that the separating layer contains a continuous phase and a particle-like filling material in a concentration of approximately 0.01 to 50 wt. % with respect to the separating layer wherein the surface of the filling particles is completely covered by the continuous phase, the continuous phase contains reticulated polyorganosiloxane and the surface of the separation layer that lies opposite to the auxiliary support has a surface roughness of approximately 400 to 50,000 nm and a mean roughness value of approximately 40 to 5,000 nm. The functional layer can be removed from the auxiliary support with minimal effort or exhibits a desirable matte surface after being separated from the auxiliary support.

The present invention concerns a multi-layer composite body, having aflexible auxiliary carrier and a separation layer arranged on at leastone side of the auxiliary carrier, which modifies the full separation orthe local limited detachment of a functional layer positioned in flatcontact with same.

A multi-layer composite body of the addressed type is, for example, theprotective foil for self-adhesive decorative surface foils,self-adhesive labels, one- or dual-sided adhesive tapes, etc. Themulti-layer composite body can constitute, as well, only a small part ofa commercial product, for example the protective foil of a self-adhesiveflap of an envelope. The multi-layer composite body can also be theprotective foil of a self-adhesive wound-dressing bandage. All theseapplications have in common that the functional layer is apressure-sensitive cement- or adhesive substance layer and the compositebody constitutes a carrier or a protective foil, which prevents soilingof the adhesive layer or unwelcome adhesion to surfaces. Beforeutilization, this carrier or protective foil is pulled off.

Another use are applications where a functional layer is produced from amelt, a solution and/or a dispersion, and the carrier is immediatelyremoved or removed subsequently with later application. In thisconnection, mention should be made of multi-layer correction ribbons,for example, for which a pigmented cover layer is formed on a carrierand, in most cases, an adhesive layer on same. This laminate serves tocover up errors in printed characters. In addition, mention can be madeof color-transfer ribbons where a color-transfer layer is arranged on acarrier. During the printing process, the color-transfer layer is, forexample, detached from the carrier and, by means of a heated print-head,transferred pictorially to a receiving substrate.

The flexible auxiliary carrier of the composite body is most frequentlypaper, however, a there is a strong trend towards foil substrates,because, based on the increased stability of foils in comparison withpaper, it is possible to reduce, for economic reasons, the thickness ofthe flexible auxiliary carrier, and, with respect to winding, forreasons of capacity. To facilitate the separation between auxiliarycarrier and functional layer, a separation is formed between auxiliarylayer and functional layer which usually contains polyorganosiloxanes.Foil substrates have the advantage here that their surface, comparedwith paper, is non-porous and lesser amounts of polyorganosiloxanes forcoating can be employed in economically beneficial manner. The lowersurface roughness, however, constitutes, at the same time, one of themajor draw-backs of the employed foil substrates, inasmuch as a smoothcarrier layer requires a smooth coating. This smooth surface leads, inturn, to problems in handling.

With respect to applications where the adhesive layer is temporarilycovered with a carrier, the smooth surface leads to full surface contactbetween adhesive layer and carrier, which, in turn, results in that thecarrier can only be detached with great effort from the adhesive layer,which, under certain circumstances, may lead, for example, to tearing oflabels.

In applications where a layer is precipitated from a liquid phase onto acarrier, one observes that the surface of the layer has an unwelcomeshiny appearance after the carrier is removed, which can be attributedto its smooth surface. The smooth surface of the transferred layers alsoleads to more difficult lettering, for example, with respect tocorrection material.

Disclosure of U.S. Pat. No. 5,165,976 is helpful for bettercomprehension of the hereinafter described invention. This patentspecification describes a substrate with a release layer. This releaselayer is obtained in that an emulsion is applied of a curable siliconesystem and a particle-shaped component, preferably a resin. Thesilicone-system is hardened under the influence of heat. Simultaneously,water is removed. As a result, a release layer with adjustableseparation effect is created for the substrate, specifically inconnection with applied adhesives. The substrate is preferably made ofpaper, preferably inexpensive, porous paper. With a content ofapproximately 35% by weight of silicone in the release layer, same ispresent in continuous phase, which envelopes the discrete particles. Alower percentage of silicone is not sufficient for envelopment of theparticles, so that the properties of the resulting mixture aredetermined by both the silicone as well as by the particles. The releaseeffect can therefore also be regulated by the quantity ratio of siliconeto particles, by the type of particles, by degree of reciprocal actionbetween silicone and particles, by cross-linkage degree of hardenedsilicone and by the coating weight. Based on the indication that an“emulsion” must be employed for coating of the substrates, one canconclude that overall a liquid system is involved, i.e. the emulsivedispersed particles, which finally are more or less embedded or bondedin the hardened silicone, do not constitute solid particles.

The silicone contents in the release layer ranges between 5 and 80% byweight, preferably between approximately 20 and 40% by weight inproportion to the total amount of the above two components. It appearsfrom all this that with presence of a larger percentage in the totalmass, the emulsive particles act counter to the release effect, i.e. theemulsive particles, if they are present, for example in the permissibleamount of 95% by weight, largely exclude the release effect or evenproduce an adhesive effect. This is documented by the type of employedparticles, for example, in form of an acrylic resin or astyrene/butadiene resin (SBR). In contrast thereto, the hereinafterdescribed invention requires the bonding of a solid filler in theseparation layer, which does not influence the properties of thesilicone, but which produces a surface roughening of the release- orseparation layer. The contents of DE 299 522 A5 largely agrees with thediscussed U.S. Pat. No. 5,165,976. By way of technological backgroundfor the present invention, mention is made of the following referencematerial: DE 27 53 675 A1, DE 41 14 964 A1, DE 38 34 007 A1, DE 26 22126 C3 and “Adhesion”, 1984, volume 9, page 18/19.

The above indicated problems with respect to the state of the art areremedied according to the invention in that the separation layercontains a continuous phase and a particle-shaped filler in aconcentration of approximately 0.01 to 50% by weight, relative to theseparation layer, whereby the surface of the filler particles aretotally covered by the continuous phase,—the continuous phase containsinter-linked polyorganosiloxanes and the surface roughness of theseparation layer, facing away from the auxiliary layer, has a roughnessdepth Rt of approximately 400 to 50000 nm and a median roughness valueof approximately 40 to 5000 nm.

By incorporating the filler, the surface of the separation layer facingaway from the auxiliary layer is made rough, so that a cross section ofthe profile shows elevations and depressions (“peaks” or “valleys”).

In one specific embodiment, the functional layer can be a layer with asmooth surface. In this case, the functional layer comes into contactonly with the “peaks” of the rough separation layer, whereby the smallercontact area permits easier detachment of the functional layer from thecomposite body. This specific embodiment is of particular interest withrespect to applications where the functional layer is an adhesive layer.Specifically, the functional layer can be a cement layer, an adhesivelayer, a transparent or tinted plastic layer, specifically a pigmentedlayer, a laminated cement layer and a transparent or tinted,specifically a pigmented layer. In another specific embodiment, thefunctional layer is in full contact with the separation layer. Afunctional layer, for example, the cover layer of a correction ribbonaccording to the invention can, correspondingly, be adjusted from“matte” dull to “translucent”. In other words, this means that thelamination, if it is subsequently detached from the separation layer,becomes duller if more peaks or valleys are formed in the filler-ladensilicone layer. With appropriately reduced roughness of the separationlayer, this dull appearance greatly recedes and can also be converted to“shiny”.

After the detachment of the functional layer from the separation layer,the now freely exposed surface of the functional layer constitutes a“negative” of the surface of the separation layer. As a result of this,a “dulled” or roughened surface of the functional layer is retained.This is of particular importance with layers which are precipitated ontoa carrier from liquid phase, for example, with color-transfer layerribbons and multi-layer correction ribbons. During the separation ordetachment of the functional layer, the separation layer remains on theauxiliary carrier.

The kind of employed filler is not critical. Examples of suitablefillers are, among others, calcium carbonate, diatomaceous earth, clays,hollow glass pearls, aluminum silicate, plastics, magnesium-carbonate,PTFE and other polymer particle-shaped materials, talcum, calcite,fibers, lime, mica, amorphous silicon dioxide, silicates, pigments, etc.The filler can be selected from a wide range of materials, whereby itshould be fully wetted by the continuous phase containing theinter-linked polyorganosiloxane, so that the entire surface of thefiller particles is wetted.

Furthermore, the filler material must not have a detrimental effect uponthe inter-linking process of the polyorganosiloxane. Also, the fillermaterial must be firmly anchored to the flexible auxiliary carrier bythe continuous phase. Basically, it is necessary—which is the goalaccording to the present invention—to totally encase the filler materialparticles in applications with highest “release effect” or separationeffect. If a so-called “controlled-release” or a given separation- orrelease effect is to be attained, it does not prove to be a hindrance ifonly a small percentage of the filler particle surface is uncovered, forexample, up to 10%. This situation will occur if a relatively highpercentage of filler material is present in the total mass, for exampleapproximately 50% and above.

Preferably employed are filler concentrations of approximately 0.01 to50% by weight, preferably approximately 0.1 to 33% by weight andspecifically approximately 0.5 to 15% by weight in proportion to theseparation layer. Material with low oil-adsorption can be employed. Highfiller contents lowers the cost of the expensive silicone layer.

The filler material may be present in form of primary particles oragglomerates, with adjustment to be made based on the effective particlediameter. The average particle size is preferably 0.01 to 20 Fm,specifically approximately 0.05 to 10 Fm, whereby an average particlesize in the range of approximately 0.01 to 8 Fm is particularlypreferred.

Application volume of the polyorganosiloxane filler mixture usually liesin the range of approximately 0.3 to 3.0 g/m², specifically up to 1.5g/m² relative to the solid matter percentage.

Selection of the filler material concentration and particle size inrelationship to the coating thickness and the targeted effects must bedone based on adhesion, cohesion and the peeling value of the layer. Byadjustment of the refractory index of the filler material to thesilicone system, it is possible to obtain a clear, roughened layer; withdifferent refractory indices, translucent surfaces can be obtained.Where transparent appearance is not important, translucent coating canbe formed in order to check the coating property of the foil on thelayer during the lamination process. In order to check the coatingproperty on the second side, it is possible to employ coloringsubstances or UV tracers.

The inclusion of filler particles in the separation layer has the resultthat the border region between separation layer and functional layer hasa roughness depth Rt of at least approximately 400 and an averageroughness value Ra of at least approximately 40 nm. According to theinvention, the Rt amounts to approximately 40 to 50000 nm, specificallyapproximately 600 to 2500 nm, and Ra approximately 40 to 5000 nm,specifically approximately 77 to 250 nm. Particularly preferred areRt-values of at least approximately 650 nm and an Ra of at leastapproximately 80 nm.

If the roughness depth Rt falls below approximately 400 nm, a more orless pronounced blocking effect sets in during the production of themulti-layer composite body or the multi-layer composite foil. In casethe roughness depth Rt of 50000 nm is surpassed, the separation layerbecomes too thick or also too rough with the result that duringsubsequent coating steps too much material would be lost, since it wouldenter into the deep valleys of the highly roughened separation layer.Corresponding considerations apply with respect to the basic conditionsfor the average roughness value Ra.

The term roughness depth Rt designates the distance between basic andreference profile of a surface profile, i.e. the maximum peak/valleydistance. The average roughness value Ra is the mean absolute distancebetween reference profile and actual profile, which is also calledcenter line average, i.e. the arithmetic average of the profiledeviations from a center line. For purposes of the invention, the Rt orRa values were ascertained by a FORM TALYSURF LASER (from RANK TAYLORHOBSON INC.) Determination of roughness was done according to BS 1134.

The average layer thickness of the separation layer preferably amountsup to approximately 3 g/m², specifically up to approximately 1.5 g/m²(in relation to solid matter percentage). The specification of layerthickness in g/m² provides information concerning the practical orcommercial application volume. This specification is usually employedwith film substrates. It means that for example the preferred layerthickness of approximately 0.5 to 2 Fm corresponds to an applicationvolume of 0.5 to 2 g/m² (in relation to the dry substance or the driedfinished coating).

Commercial polysiloxane-systems can be classified intosolvent-containing, also water systems, and solvent-free systems, whichcan be hardened or inter-connected by heat, by UV light, and by ionicbeams. Standard methods can be used for application of thesepolysiloxane-containing layers to the flexible carrier such as: gravureprint (direct, indirect roller application with several rollers)Meyer-wiper-blade, reverse roll, multi-roll coating (for example 5-rollcoater) etc. After application of the polysiloxane layer, same issubjected to an inter-linking step.

The inter-linkable polyorganosiloxane-systems constitute systems withflow capability, containing functional groups with a multitude ofinter-link possibilities. They are particularly accessible to thermalinter-linking induced by UV light or by ionic beam. In addition,inter-linking catalysts, such as peroxide, azo-compounds ororgano-metallic compounds may be added. Technically highly important isthe so-called peroxide inter-linking with the aid of radical formers,such as for example bis-(2.4-dichlorobenzoyl)-peroxide,di-benzoyl-peroxide, di-cumyl-peroxide, tert-butyl-perbenzoate or2.5-bis-(tert-butyl-peroxy)-2.5-dimethylhexane.

Further being considered as polyorganosiloxane-systems arepolyorganosiloxanes which contain per molecule at least two alkenyl- oraralkenyl groups, bonded to Si-atoms. Polyalkyl-alkenyl-siloxanes orpolyaryl-alkenyl-siloxanes are named as example. In this case, thenumber of carbon atoms in the alkyl group lies preferably in the rangefrom 1 to 18. Preferred examples for alkyl- or aryl groups are methyland phenyl. Examples for the alkenyl groups are vinyl and allyl. Themolar proportion of the alkyl or aryl groups to the alkenyl groups inthe polyalkyl-alkenyl-siloxane or polyaryl-alkenyl-siloxane liespreferably in the range from 0.02 to 0.3 mol-%. Catalysts of theplatinic type can be employed as interlinking catalysts, for examplechloro-platinic acid in order to enhance the polymerization of thealkenyl groups.

Vinyl-group containing polyorgano-siloxanes can also be inter-linkedwith sulfur. The contents of vinyl groups of interlinking siliconesshould amount 1 to 4 mol-% and the amount of sulfur 2%.

Polyorganosiloxanes can also be interlinked to double bonds via additionreaction of Si—H . The employed catalysts are precious metal salts and-complexes, whereby the platinic derivatives are the most important.

Mercapto-functional polysiloxanes can be produced photo-chemically byaddition of HS-groups to allyl- or vinyl-groups, in the presence ofphoto-initiators. Preferred mercapto-alkyl rests have a carbon number inthe range from 1 to 4, whereby the other organic rests of themercapto-functional poly-siloxanes preferably have between 2 to 3 carbonatoms or are phenyl. The methylvinyl-polysiloxane to be thereby broughtto reaction preferably carries approximately 3 vinyl groups per moleculeand is employed in such volume that one obtains 0.2 to 1.0 Si-boundvinyl rests per Si-bound mercapto-alkyl rest. If necessary, it ispossible to incorporate a customary gelling inhibitor, such asde-hydroxy-phenoles and their alkyl-derivatives, also, perhaps, aphoto-sensitizer, such as, for example, aromatic ketones, likeacetophenone or benzophenone, or azo-compounds, such asazo-bis-isobutyric acid nitrile. Suitable systems are evident, forexample, from DE-PS 26 126. Epoxy-functional poly-organosiloxanes canalso be interlinked in the presence of photo-chemically produced Lewisacids, for example from p-chlorobenzol-diazonium-hexafluoro-phosphate.Acryl-group containing silicones can also be photochemicallyinterlinked.

Preferred methods employ UV radiation. The reasons are that only lowheat is used and the foil is thus not exposed to the danger of warping,whereby a lesser thickness can be used. UV-interlinkable systems usuallyhave a low viscosity and can therefore more easily be modified withadditives.

The interlinking mechanism is largely insensitive to mixed-in additives.It is possible to add larger amounts of filler material withoutaffecting the coating capability.

Interlinking with ã- and ã-rays takes place via the formation of freeradicals. Instead of ã-rays, it is also possible to work with ionicbeams. Condensation interlinking also plays a role in the interlinkingof polyorganosiloxanes. A silicone-bound hydroxyl group reacts with agroup R, bound to silicone, which can, for example, be an alkoxy-,acyloxy-, amino-, hydroxy-, oximo- or amido group R, while HR is beingsplit off. Depending upon the activity of the interlinking agent, thereaction takes place either with or without catalysts, so that eithertwo-component systems are formulated or one-component systems. Thestandard commercial interlinkers mostly consist of mixtures from silicicacid esters and tin-catalysts, such as, for example,dibutyl-tin-diacetate, dioctyl-tin-maleinate, tin-(II)octoate orreaction products of these components or multi-valent isocyanates. AnSi—H-group can react in the presence of basic catalysts or of Sn- andPt-compounds with sinanol-groups, simultaneously developing hydrogen. Byselection of type and amount of polysiloxane starter materials, it ispossible to modulate the release capability of the separation layer.This aspect is of particular importance if a composite layer arrangementexists with several functional/separation layer border areas, which mustbe detached in pre-determined sequence. This case occurs regularly whenthe composite material is wound up into a roll. For proper un-rolling itis indispensable that the functional layer has less adhesion vis-a-visthe next loop than vis-a-vis the assigned separation layer. For thatpurpose, it is preferred that on the reverse side of the auxiliarycarrier another separation layer is formed, which has higher releasecapability (separation layer with 100% release) than the (separationlayer with controlled release) arranged between auxiliary carrier andfunctional layer. Said reverse-side separation layer is preferablylikewise obtained according to the invention. Such formation of areverse-side separation layer is also preferred in order to facilitatethe transport of the composite body over rollers and smooth surfaces.

The auxiliary carrier preferably is a plastic foil, specifically ofthermo-plastic material. Suitable as well are paper carriers and othercarrier materials known in the state of the art. Particularly suitableplastic foils consist for example of thermoplastic polyesters orpolyolefins. To be named as particularly suitable starter materials forsame are, among others: polyalkylene-terephthalates, such aspolyethylene-terephthalate, polybutylene-terephthalate orpoly(1.4-cyclohexanedimethylene-terephthalate) polyethylene,polypropylene, polybutene, polyisobutene, polystyrene, cellulosederivatives, such as specifically cellulose acetate, cellulose butyrateand cellulose propionate and co-extrudates of, for example,polyethylene/polypropylene and laminates of, for example, paper andpolyethylene, polyvinylacetate, polyvinylchloride, polyvinylalcohol,polyvinylbutyral, polyamide, ethylene-vinylacetate-copolymerisate, PEN,acrylnitrile/butadiene/styrene-copolymerisate (ABS),acryinitrile/styrene/acryl-ester-copolymerisate (ASA),styrene/acryl-nitril-copolymerisate (SAN), polycarbonate, polyamide,PEEK, nylon.

Preferred foils have a thickness of approximately 2 to approximately 400Fm, specifically approximately 3.5 to 100 Fm and particularly preferredof approximately 3.5 to 50 Fm.

It has been shown, when producing silicone coated composite materialshaving a carrier, that when the manufacturing is done on a roller system(any selected coating system) there will be no significant problem withrespect to the paper because of trapping of air. The situation isdifferent, however, if the paper carrier is replaced by a plasticcarrier or a foil carrier, which has no trapped air, but a smoothsurface. In this case, there sets in a type of “eraser or rubbereffect”, so that it is impossible to pass the coated strip in thedesired fashion over the different rolls of the coating system. It ispossible, for example, based on said effect, that detrimental blockingoccurs.

If this material is transferred to a jumbo-roller, there will occur, inaddition, unwelcome tensions of the foil, as a result of which, thedesired ‘flatness’ of the coated films is partially eliminated (crinklyappearance). These undesired symptoms have a further detrimental effectif the composite films or laminates are to be coated at a later date forexample with an adhesive and they occur specifically in connection withthe coating of polyolefin films, which have a greater elasticitycompared, for example, with polyester films. These problems arecompletely eliminated according to the invention by the incorporation ofpigments.

In addition, the invention has the following benefits: Due to thesurface roughness of the separation layer, a multitude of drawbacks areavoided or at least minimized relative to separation layers of knowncomposite structures. When sliding on stationary surfaces or rollers,the contact area vis-a-vis the composite body according to the inventionis greatly minimized, which greatly suppresses the development offriction elasticity. Consequently, the separation layer has improvedsliding behavior on static surfaces, which results in reducedelectrostatic charging and in reduction or exclusion of problems relatedtherewith, or in exclusion of oxidation of the upper surface foil, basedon electrostatic discharge and the thereby caused irregularities of anysubsequently applied coatings. When sliding along-side stationarysurfaces or rollers, the contact surface towards the composite bodyaccording to the invention is greatly reduced, which greatly suppressesthe formation of friction electricity.

When manufacturing the composite body according to the invention,transport of the auxiliary carrier over rollers or along smooth surfacesis made easier. In applications where the composite bodies according tothe invention are employed for temporarily covering an adhesive layer,same comes into contact only with the “peaks” of the rough separationlayer, whereby the smaller contact surface facilitates easier detachmentor easier release from the composite body. In applications where afunctional layer is produced on the carrier from a melt, a solutionand/or a dispersion, a desirable matt (dull) surface of the functionallayer is obtained, following the release from the carrier. As anexample, one can cite a multi-layer correction ribbon which serves forcovering up mistakes in printed characters. The exposed surface of thefunctional layer, following separation from the auxiliary carrier,represents a“negative” of the separation layer surface, therebyobtaining a matted [dulled] or roughened-up surface of the functionallayer.

The microscopically rough surface appears pleasantly “matt” to theviewer. In case of a correction ribbon, it can, for example, easily bere-inscribed, whereby when inscribing is done with ink or China-ink, thedanger of smearing is reduced or even eliminated and inscription withpencil is particularly facilitated, since due to the surface roughness,there is improved pencil lead abrasion.

It is of particular benefit with respect to the invention that incomparison with separation layers containing no filler materials, theapplication volume of polyorganosiloxane can be significantly reduced,which constitutes an important cost benefit. One outstanding benefitconsists in that the functional layer of a multi-layer composite bodycan be detached with minimum effort, whereby, after separation, thefunctional layer presents the desirable degree of surface-“dullness”.Another outstanding benefit—already addressed as well—consists in thatthe multi-layer composite body according to the invention slides veryeasily over rollers or stationary surfaces, for example in color tapecassettes or reel-off instruments. It is emphatically pointed out thatthe invention improves all teachings described initially in connectionwith the state of the art.

Thus, these known teachings, respectively developed further according tothe invention, shall likewise constitute the object of the presentinvention.

The surface roughness of the separation layer can also be beneficiallyutilized in regulating the initial adhesion of the transferred adhesivegum layer. This is schematically depicted in FIGS. 3 and 4. Transfer ofan adhesive gum layer to a paper substrate 2 is shown, whereby theadhesive gum layer 1 is released in FIG. 3 from a customary carriermaterial 4, either by means of a smooth separation layer 3, and in FIG.4 by a roughened-up separation layer 3, according to the invention. Theinstantaneous adhesive action of the rough side of the transferredadhesive substance layer is diminished, since the contact surface with asecond substrate is restricted to the “peaks” of the adhesive substancelayer. This permits, for example, removal and re-positioning in case theinitial placement was incorrect. With pressing, however, the viscousmelt-adhesive layer is compressed, so that a comparable final adhesivestrength is obtained, as in the case depicted in FIG. 3.

The invention is explained in more detail by means of the attacheddrawings and the following examples:

FIG. 1 represents a specific embodiment of the invention in which afunctional layer, having a smooth surface 1, comes only into contactwith the “peaks” of the rough separation layer 2.1 of a multi-layercomposite body, having, in addition, a flexible auxiliary carrier 2.2,so that air-filled spaces are created. The small contact area 4 permitseasy removal of the functional layer from the composite body 2. Theseparation layer contains a continuous phase 2.1.1, containing aninter-linked polyorganosiloxane and a particle-like filler substance2.1.2.

FIG. 2 depicts a rough functional layer 10, which is in full contactwith the separation layer 2.1, which contains a continuous phase 2.2.1,containing an interlinked polyorganosiloxane and a particle-like fillersubstance 2.1.2. The separation layer 2.1 and the auxiliary carrier 2.2form together the composite body 2 according to the invention. Followingthe separation of the functional layer from the separation layer(indicated on the left side of FIG. 2), the exposed surface represents a“negative” of the separation layer surface.

This results in obtaining a “dulled” or roughened-up surface of thefunctional layer.

In the following examples, coating masses were produced by mixingtogether the respectively specified components. These were applied byreverse coating to a polyester foil having a thickness of 20 Fm. Theobtained coatings of examples 1 to 3 were subjected to UV-hardening. Thesilicone coating of Example 4 was hardened by means of ionic beam. Thecoatings of the examples 5 to 7 were thermally hardened, by heating themfor 10 seconds at 110° C.

Subsequently, the friction coefficients of the obtained carriermaterials were measured according to ASTM D1894/87. A lower frictioncoefficient value indicates low friction during transport over rollersand smooth surfaces and leads to the therewith connected benefitsrepresented in the description. In this specific embodiment, it is ofbenefit if both sides of the flexible auxiliary carrier are coated withthe separation layer, so that the reverse side of the composite body,which is not in contact with a functional layer, is also provided with aseparation layer. The experimentally ascertained roughness depth Rtalways ranged approximately 400 to 50000 nm and the average roughnessvalue Ra between approximately 40 to 5000 nm.

EXAMPLE 1

Separation Layer with 100% Release without Filler Material (UV-System)

Comparative Example

Solvent-free Methylpolysiloxane

Solvent-free Methylpolysiloxane UV 9500 G.E. Silicones Co. 15.0 wt. pts.capable to undergo addition-reactions Solvent-free Methylpolysiloxane UV9400 G.E. Silicones Co. 15.0 wt. pts. capable to undergoaddition-reactions Photoinitiator UV 9380C G.E. Silicones Co. 0.6 wt.pts. Adhesion-friction coefficient:*) Sliding-friction coefficient:*)*)- These values were outside the measuring range, value > 3.0

EXAMPLE 2

Separation Layer with 100% Release with Filler Material (UV-hardenable)

Solvent-free Methylpolysiloxane UV 9500 G.E. Silicones Co. 15.0 wt. pts.capable to undergo addition-reactions Solvent-free Methylpolysiloxane UV9400 G.E. Silicones Co. 15.0 wt. pts. capable to undergoaddition-reactions Photoinitiator UV 9380C G.E. Silicones Co. 0.6 wt.pts. Silicone dioxide,particle diameter approximately 2Fm Syloid ® 244Grace GmbH 1.2 wt. pts. Adhesion-Friction Coefficient 0.27Sliding-friction Coefficient 0.28

EXAMPLE 3

Separation Layer with Controlled Release with Filler Material(UV-hardenable)

Solvent-free Methylpolysiloxane UV 9500 G.E. Silicones Co. 15.0 wt. pts.capable to undergo addition-reactions Solvent-free Methylpolysiloxane UV9400 G.E. Silicones Co. 15.0 wt. pts. capable to undergoaddition-reactions Release controlling agent UV 9430 G.E. Silicones Co.70.0 wt. pts. Photo-initiator UV 9380C G.E. Silicones Co. 0.6 wt. pts.Silicone dioxide, particle diameter approximately 7 nm Aerosil > 380Degussa AG 3.0 wt. pts. Adhesion-friction coefficient 0.18Sliding-friction coefficient 0.23

EXAMPLE 4

Separation Layer with 100% Release with Filler Material (Ionic-beamHardened)

Solvent free Methylpolysiloxane RC450 TH Goldschmidt AG 100 wt. pts.capable to undergo addition reactions amorphous silicone dioxide,particle Syloid ED3 ® Grace GmbH 2 wt. pts. diameter approximately 3FmAdhesion-friction Coefficient 0.22 Sliding-friction Coefficient 0.28

EXAMPLE 5

Separation Layer with 100% Release with Filler Material (ThermalHardening)

pre-catalyzed, solvent-free Dow 7702* Dow Corning Corp. 100 wt. pts.polysiloxane with functional groups, capable of undergoing additionreactions Interlinking Agent Dow 7215* Dow Corning Corp. 6 wt. pts. PureSilicone-dioxide, particle diameter approx. 4-8 Fm TK 900 Degussa AG 2wt. pts. Adhesion-friction coefficient 0.24 Sliding-friction coefficient0.26

EXAMPLE 6

Separation Layer with Controlled Release with Filler Material (ThermalHardening)

Solvent-free Methylpolysiloxane, Dehesive 920 ® Wacker GmbH 27.0 Wt.Pts. capable of undergoing addition reactions Release Controlling AgentCRA 17 Wacker GmbH 33.0 wt. pts. Interlinking Agent Interlinker 24Wacker GmbH 2.4 wt. pts. Catalyst Catalyst OL Wacker GmbH 1.05 wt. pts.Adhesion Provider HF 86 Wacker GmbH 0.27 wt. pts. Hydrophobic QuartzDust, HDK H-15 Wacker GmbH 0.60 wt. pts. particle diameter approx. 4 FmAdhesion-friction coefficient 0.30 Sliding-friction coefficient 0.33

EXAMPLE 7

Separation Layer with 100% Release with Filler Material (ThermalHardening

Polymethylpolysiloxane Dehesive 810 Wacker GmbH 15.0 wt. Pts. capable ofcondensation polymerization Solvent White Spirit 84.0 wt.pts.Interlinking Agent V-83 Wacker GmbH 0.7 wt.pts. Catalyst C 80 WackerGmbH 0.3 wt.pts. Alumo-silicatton, particle diameter approx. 4 Fm Huber95 Huber Co. 0.3 wt.pts. Adhesion-friction Coefficient 0.30Sliding-friction Coefficient 0.33

What is claimed is:
 1. Multi-layer composite body comprising a flexible auxiliary carrier and a separation layer arranged on at least one side of said flexible auxiliary carrier, said separation layer in flat contact with a functional layer and modifying the complete or locally limited separation of said functional layer, said separation layer comprising a continuous phase and a particle filler substance in a concentration of approximately 0.01 to 50% by weight relative to the separation layer, whereby the surface of the filler substance particles is completely covered by the continuous phase, the continuous phase comprising an interlinked polyorganosiloxane, and the roughness of the separation layer surface facing away from the auxiliary carrier has a roughness depth Rt of approximately 400 to 50000 nm and an average roughness value of approximately 40 to 5000 nm.
 2. Composite body according to claim 1, wherein the average thickness of the separation layer is up to approximately 3 g/m² thick.
 3. Composite body according to claim 1, wherein the particle size of the filler substance is approximately 0.01 to 20 Fm.
 4. Composite body according to claim 3, wherein the particle size of the filler substance lies within a range of approximately 0.05 to 10 Fm.
 5. Composite body according to claim 1, wherein the average particle size of the filler substance lies within a range of approximately 0.1 to 8 Fm.
 6. Composite body according to claim 1, wherein the roughness depth Rt is approximately 600 to 2500 nm and the average roughness value approximately Ra 77 to 250 nm.
 7. Composite body according to claim 1, wherein the roughness depth Rt is at least approximately 650 nm and the average roughness value Ra at least approximately 80 nm.
 8. Composite body according to claim 1, wherein the particle filler substance comprises calcium carbonate, diatomaceous earth, clays, hollow glass pearls, aluminum silicate, plastics, magnesium carbonate, particle-forming polymer materials, specifically polytetrafloroethylene, talc, fibers, calcite, lime, mica, amorphous silicone dioxide and/or silicates.
 9. Composite body according to claim 1, wherein the auxiliary carrier is a plastic foil.
 10. Composite body according to claim 9, wherein the plastic foil is made of thermoplastic polyester and/or polyolefin.
 11. Composite body according to claim 1, wherein the inter-linked polyorganosiloxane is produced by radical inter-linking of a polyorganosiloxane containing per molecule at least two alkyl-groups bonded to Si-atoms.
 12. Composite body according to claim 1, wherein the inter-linked polyorganosiloxane is obtained by inter-linkage of an polyorganosiloxane with H-atoms bonded to Si-atoms and a polyorganosiloxane with alkenyl-groups bonded to Si-atoms.
 13. Composite body according to claim 1, wherein the inter-linked polyorganosiloxane is produced from a polyorganosiloxane which contains groups capable of being hydrolyzed to silanol groups.
 14. Composite body according to claim 1, wherein said composite body further comprises a functional layer on the separation layer.
 15. Composite body according to claim 14, wherein the functional layer is an adhesive layer, a transparent or tinted plastic layer, specifically a pigmented plastic layer, a laminate from an adhesive layer and a transparent or tinted, a pigmented layer.
 16. Method for the manufacture of a multi-layer composite body according to claim 1, in which a mixture of a polyorganosiloxane, containing inter-linkable groups with a particle filler substance, is applied according to a known method onto a flexible auxiliary carrier and inter-linkage of the polyorganosiloxane is subsequently realized.
 17. Method according to claim 15, the step of inter-linkage is realized thermally by means of UV light or ionic beam.
 18. Multi-layer composite body comprising a flexible carrier, a separation layer arranged on at least one side of said flexible carrier, and a functional layer arranged on said separation layer, said separation layer comprising a continuous phase and 0.01 to 50% by weight filler, the surface of the filler being completely covered by the continuous phase, the continuous phase comprising an interlinked polyorganosiloxane, and a roughness of the separation layer surface facing away from the carrier having a roughness depth Rt of approximately 400 to 50000 nm and an average roughness value of approximately 40 to 5000 nm. 